#include "memory.h"
#include "slice.h"
#include <stdlib.h>
#include <stdio.h>

static int
strings_len(Token *list)
{
	int len = 0;
	for (Token *e = list; e != NULL; e = e->next)
		if (e->type == TOK_GROUP)
			len += strings_len(e->group.tokens);
		else if (e->type == TOK_STRING)
			len += slice_len(e->slice) + 1;
	return len;
}

static int
strings_cat(char *mem, Token *list, int off)
{
	for (Token *e = list; e != NULL; e = e->next)
		if (e->type == TOK_GROUP)
			off = strings_cat(mem, e->group.tokens, off);
		else if (e->type == TOK_STRING) {
			slice_cpy(mem + off, e->slice);
			e->string_ptr = off;
			off += slice_len(e->slice) + 1;
		}
	return off;
}

int
memory_create(Memory *memory, Token *list)
{
	const int len = strings_len(list);
	memory->strings = malloc(len);
	if (memory->strings == NULL) {
		perror("memory_create:malloc");
		return 1;
	}
	const int cated = strings_cat(memory->strings, list, 0);
	if (cated != len) {
		fprintf(stderr, "strings_cat wrote %d bytes instead of %d",
		        cated, len);
		free(memory->strings);
		memory->strings = NULL;
		return 1;
	}
	return 0;
}

void
memory_destroy(Memory *memory)
{
	if (memory->strings != NULL) {
		free(memory->strings);
		memory->strings = NULL;
	}
}